The shortening of telomeres in cells was thought to be an important biomarker for lifespan and aging. The edible dormouse (Glis glis), a small hibernating rodent, now turns everything upside down. In contrast to humans and other animals, telomere length in the edible dormouse significantly increases in the second half of its life, as researchers from Vetmeduni Vienna found out just recently.
The study was published in Scientific Reports.
“As far as I know, no previous study has reported such an effect of age on telomere lengthening,” says Franz Hoelzl, one of the authors. Apparently, this unique pattern is due to the peculiar life history of this species. They can reach maximum lifespan of 13 years, which is a Methuselah-like age for a small rodent. “This extreme lifespan is almost certainly related to their ability to rejuvenate telomeres”, says Hoelzl. Telomeres are the endcaps of chromosomes, which prevent, together with proteins, the degradation of coding DNA sequences.
Telomeres in small animals shorten fast, but in edible dormice they even grow
In normal somatic cells, telomeres are shortened with every cell division. Besides, oxidative stress has a strong effect on telomere erosion. However, the rate of telomere shortening differs between species. For instance, it has been shown before that telomeres in fast-aging, short-lived wild animals erode more rapidly than in slow-aging, long-lived species.
Earlier this year, the author Franz Hoelzl and his colleagues from Vetmeduni Vienna showed that edible dormice has the capability to re-elongated its telomeres, given that food availability is high. This finding raised the question about the long-term balance between telomere attrition and repair.
The relative telomere length (RTL) gave evidence
To find an answer, the team started a long-tem study on changes in telomere length. In the Vienna Woods in Austria they regularly checked 130 nest-boxes that are occupied by free-living dormice. The researchers collected the rodent’s buccal mucosa for three years. Thus, they could extract the DNA and determine the relative telomere length for each dormouse individually using qPCR. With this method scientists can define the amount of target DNA compared to a reference gene of the same sample.
Elongation does not only occur, it even increases in older edible dormice
“We found out that the telomeres were shortened in young animals but length significantly increased once the dormice were six years old or older. To top it all, the rate of telomere elongation also increased with increasing age of the dormice”, says Franz Hoelzl.
Among the variables tested, only age significantly affected RTL in a non-linear pattern with telomere length decreasing in younger and increasing in older dormice. Hoelz says, “Telomere length was not affected by time of the year, sex, body mass or reproductive activity at the time of sampling.” Nevertheless, the analysis of long term reproduction-data of the same population shows that the probability to reproduce also increases with age. This finding could indicate that telomere elongation is actually part of the preparation for upcoming reproductive events, as gestation and lactation could increase oxidative stress and the animals may attempt to protect their genome.
The Latest on: Telomeres
via Google News
The Latest on: Telomeres
- Telomeres, trauma, and mindfulnesson August 10, 2019 at 7:30 pm
The connection between our minds and bodies determines our health and well-being, and the rate at which our cells age and die can be influenced by lifestyle choices. We hear about keeping our genes in ...
- Tpz1 TPP1 prevents telomerase activation and protects telomeres by modulating the Stn1-Ten1 complex in fission yeaston August 7, 2019 at 2:21 am
In both mammalian and fission yeast cells, conserved shelterin and CST (CTC1-STN1-TEN1) complexes play critical roles in protection of telomeres and regulation of telomerase, an enzyme required to ...
- Dr Max Douglason August 5, 2019 at 10:34 am
He is the holder of the CR UK Career Development Fellowship and his research focuses on the replication and processing of telomeres. Team: Telomere Replication On completing an undergraduate degree in ...
- Research overviewon August 5, 2019 at 10:33 am
Telomeres are nucleoprotein caps that protect the ends of eukaryotic chromosomes from repair processes and DNA damage. Each cell cycle, these complex, dynamic structures are copied and reassembled ...
- How to Extend Your Telomeres to Slow down and Reverse Human Ageing - Life Extensionon July 23, 2019 at 7:05 pm
We are currently galloping full speed along an exponential curve that unlike the neural nets of the 1990's, that promised a lot but delivered very little, this time it really looks like we are on the ...
- How Focusing on the Present Can Keep Your Cells Healthyon July 23, 2019 at 8:50 am
What are telomeres? They are tiny protective sheaths that are located at the tips of our chromosomes. Telomeres help protect chromosomes, allowing them to replenish and replicate. They've been ...
- Size does matter when it comes to telomereson July 8, 2019 at 6:33 am
One of the more novel studies from the Child Health CheckPoint was the measurement of 'telomeres' – the tiny caps on each strand of our DNA, which serve to protect the ends of our chromosomes. Led by ...
- What are Telomeres?on May 21, 2019 at 9:02 pm
Telomeres are crucial parts of the chromosome that act to protect them and ensure DNA replication is performed effectively. Mutations and defects with telomeres can cause a multitude of health ...
- Study finds direct oxidative stress damage shortens telomereson May 14, 2019 at 8:01 am
The same sources thought to inflict oxidative stress on cells—pollution, diesel exhaust, smoking and obesity—also are associated with shorter telomeres, the protective tips on the ends of the ...
via Bing News